EVM-38: EvmMicrometerMetricsRecorder

[Puneethkumarck]

Context

The EVM metrics recorder exposes Prometheus counters for observability of the indexer pipeline. It follows the same MetricsRecorder pattern used by the Solana indexer, providing a recordBatch convenience method that increments multiple counters from a single EvmBatchResult.

Specification

• Layer: Infrastructure (infrastructure/metrics/EvmMicrometerMetricsRecorder.java)
• 12 Prometheus counters:
  • evm_blocks_processed — blocks successfully processed
  • evm_tx_received — transactions received from stream
  • evm_tx_written — transactions written to DB
  • evm_tx_failed — failed transactions recorded
  • evm_transfers_native — large native transfers detected
  • evm_transfers_token — ERC-20 token transfers detected
  • evm_accounts_written — accounts upserted
  • evm_reorgs_detected — chain reorganizations detected
  • evm_batches — batch flush operations
  • evm_rpc_calls — JSON-RPC calls made
  • evm_rpc_errors — JSON-RPC errors encountered
  • evm_blocks_backfilled — blocks fetched during gap backfill
• Convenience method: recordBatch(EvmBatchResult result) — increments evm_tx_written, evm_tx_failed, evm_transfers_native, evm_transfers_token, and evm_batches from the batch result fields
• Individual record methods for counters not covered by batch result (blocks, reorgs, rpc calls, etc.)

Acceptance Criteria

• All counters registered with Micrometer MeterRegistry
• recordBatch increments written, failed, native transfers, token transfers, and batches counters
• Individual record methods increment their respective counters
• Unit tests use SimpleMeterRegistry to verify counter values after recording

Dependencies

• EVM-13: EvmBatchResult domain model (input to recordBatch)

References

• docs/evm-implementation-plan.md — Phase 4: EVM Infrastructure — Metrics & Console
• docs/evm-functional-spec.md
• docs/CODING_STANDARDS.md